Drug deactivation system and method of deactivating a drug using the same

ABSTRACT

A drug deactivation system according to some embodiments includes at least one degradable capsule exposed to at least one drug-retaining region of a drug delivery device and an agent. The agent is configured to render a drug ineffective upon degradation of the at least one capsule. The at least one drug-retaining region is configured to retain one of the drug and the agent and the at least one capsule is configured to retain the other of the drug and the agent.

TECHNICAL FIELD

Embodiments exemplarily described herein are generally related tosystems configured to deactivate drugs, more particularly, to a drugdeactivation system configured to render a drug within a drug-retainingregion of a drug delivery device ineffective.

BACKGROUND

Generally, drug delivery devices (such as inhalers, syringes,intravenous bags, implantable drug delivery systems, transdermalpatches, pill bottles, liquid medicine bottles, eyedroppers, etc.) storedrugs until the drugs are required by a user. There are numerousoccasions when it would be desirable to render the drugs containedwithin such drug delivery devices ineffective either automatically ormanually in order to prevent the drug from being improperly releasedinto the public (e.g., though the public water supply, through thegarbage, etc.) or improperly obtained (e.g., through tampering of thedrug delivery device).

It was the understanding and recognition of these and other problemsassociated with the conventional art that formed the impetus for theembodiments exemplarily described herein.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A and 1B are plan views schematically illustrating an exemplaryembodiment of a drug deactivation system according to an embodiment;

FIGS. 2A and 2B are plan views schematically illustrating anotherexemplary embodiment of a drug deactivation system according to anotherembodiment;

FIGS. 3A and 3B are plan views schematically illustrating anotherexemplary embodiment of a drug deactivation system according to anotherembodiment;

FIGS. 4A and 4B are plan views schematically illustrating anotherexemplary embodiment of a drug deactivation system according to anotherembodiment;

FIG. 5 is a plan view schematically illustrating a drug deactivationsystem according to another embodiment; and

FIG. 6 is a plan view schematically illustrating a drug deactivationsystem according to another embodiment.

DETAILED DESCRIPTION OF THE EMBODIMENTS

FIGS. 1A and 1B are plan views schematically illustrating an exemplaryembodiment of a drug deactivation system according to an embodiment.

Referring to FIG. 1A, a drug deactivation system may be implemented witha drug delivery device including a drug-retaining region 10 within whicha drug 12 is retained. The drug delivery device may be provided as aninhaler, a syringe, an intravenous bag, an implantable drug deliverysystem, a transdermal patch, a pill bottle, a liquid medicine bottle, aneyedropper, or the like or a combination thereof. An exemplarydiscussion of drug delivery devices capable of use with the embodimentsdisclosed herein can be found in co-pending U.S. patent application Ser.No. 12/356,824, entitled “SENSOR SYSTEM FOR DRUG DELIVERY DEVICE, DRUGDELIVERY DEVICE HAVING THE SAME AND METHOD OF USING THE SAME,” thedisclosure of which is incorporated herein by reference in its entirety.Accordingly, a drug delivery device may, for example, include a housingwithin which the drug-retaining region is located.

As will be exemplarily described in greater detail below, the drug 12may be rendered ineffective in the presence of an agent. As used herein,the term “drug” refers to any material intended for use in thediagnosis, cure, mitigation, treatment, or prevention of disease in ahuman or other animal, or any material (other than food) which affectsthe structure or any function of the body of a human or other animal.Thus, a drug is rendered “ineffective” when its intended use isprevented from being realized by the user.

In the illustrated embodiment, the drug neutralization system mayinclude a plurality of capsules 14 exposed to the drug-retaining region10. The capsules 14 may be distributed throughout the drug-retainingregion 10. Each of the capsules 14 may include a reservoir. An agent 16may be retained within the reservoir of the capsule 14. As will bedescribed in greater detail below, the capsules 14 are degradable.Accordingly, the agent 16 may be supplied to the drug 12 when thecapsules 14 become degraded. The agent 16 is configured to render thedrug 12 ineffective when the agent is supplied to the drug 12. However,when the capsules 14 are not degraded or are in a substantiallynon-degraded state, the agent 16 is isolated from the drug 12 so thatthe drug 12 is not rendered ineffective.

In the illustrated embodiment, the capsules 14 are the same shape andsize. It will be appreciated, however, that the capsules 14 may havedifferent shapes and/or sizes. In the illustrated embodiment, thecapsules 14 are spherical. It will be appreciated, however, that thecapsules 14 may have substantially any shape. It will also beappreciated that the number, size and shape of the capsules 14 exposedto the drug-retaining region 10 may be selected to ensure that asufficient amount of agent 16 can be provided to render the drug 12within the drug-retaining region 10 ineffective. Indeed, the capsules 14may be replaced with a single capsule 14 retaining substantially thesame amount of agent 16 as each of the capsules 14 combined.

Referring to FIG. 1B, the capsules 14 shown in FIG. 1A become degradedupon receiving energy supplied from an energy source, as will bedescribed in greater detail below. Generally, however, energy capable ofdegrading the capsules 14 may include electrical energy, thermal energy,chemical energy, mechanical energy, electromagnetic radiation, magneticenergy, or the like or a combination thereof. The degraded capsules areidentified at 18 with dashed lines to represent degradation of thematerial forming the capsules 14. As exemplarily illustrated, thecapsules 14 are partially degraded to form degraded capsules 18. It willbe appreciated, however, that at least some of the capsules 14 may befully degraded, in which case the degraded capsules 18 would not exist.

When the capsules 14 are degraded, the agent 16 retained therein isreleased into the drug-retaining region 10. In one embodiment, agent 16released from the degraded capsules 18 may migrate within the drug 12via self-diffusion or forced-diffusion (e.g., within a chemicalgradient, a force gradient, an electrical potential gradient, or thelike or a combination thereof). Upon being released into thedrug-retaining region 10, the agent renders the drug 12 shown in FIG. 1Aineffective. The ineffective drug is identified at 20. In oneembodiment, the agent 16 binds to the drug 12 to render the drug 12ineffective. In another embodiment, the agent 16 binds to receptors ofthe drug 12 to render the drug 12 ineffective. For example, the drug 12could be morphine and the agent 16 could be cyprodime (an opioidreceptor antagonist). In yet another embodiment, the agent 16 chemicallydegrades the drug 12 to render the drug 12 ineffective. For example, thedrug 12 could be insulin and the agent 16 could be a strong acid orbase. Table 1 identifies exemplary materials of which the agent 16 maybe comprised, depending on some exemplary drugs that may be retainedwithin the drug-retaining region 10.

TABLE 1 Medical Drug retained within drug- Application retaining region10 Agent 16 Pain morphine, codeine Cyprodime, Naltrindole, managementhydromorphone, Norbinaltorphimine, hydrocodone, oxycodone, Hydrogenperoxide, oxymorphone, metabolizing enzymes such desomorphine, as NADHand NADPH, diacetylmorphine, caustic reactants, such as nicomorphine,NAOH, KOH, dipropanoylmorphie, trimethylamine benzylmorphine, pethidine,methadone, tramadol, propoxyphene, endorphins, enkephalins, dynorphins,endomorphins. Antibiotics Penicillin, cephalosporins, β-lactamaseenzyme, strong other β-lactam antibiotics, acids, strong basesAminoglycosidic antibiotics fluoroquinolones, nitrofurans, vancomycin,monobactams, co- trimoxazole, metronidazole anti- Aldehydes, Aromaticallylic Strong acids, strong bases convulsants alcohols, Barbiturates,Benzodiazepines, Bromides, Carbamates, Carboxamides, Fatty acids,Fructose derivatives, Gaba analogs, Hydantoins, Oxazolidinediones,Propionates, Pyrimidinediones, Pyrrolidines, Succinimides, Sulfonamides,Triazines, Ureas, Valproylamides Reproductive Amine-derived Strongacids, strong bases, Hormones hormones: hydrolytic enzymescatecholamines, thyroxine; Peptide hormones: TRH, vasopressin; Proteinhormones: insulin, growth hormone, luteinizing hormone,follicle-stimulating hormone, thyroid- stimulating hormone;testosterone, cortisol, calcitriol

In one embodiment, at least one of the capsules 14 may be formed of amaterial capable of chemically binding with the agent 16. In such anembodiment, the material may be porous and may be degraded when suppliedenergy (e.g., electrical energy, mechanical energy, or the like or acombination thereof) overcomes a binding potential of the agent 16 tothe porous material of the at least one of the capsules 14. In thismanner, the at least one of the capsules 14 is “degraded” because it canno longer bind the agent 16 and can no longer retain the agent 16.

FIGS. 2A and 2B are plan views schematically illustrating an exemplaryembodiment of a drug deactivation system according to anotherembodiment.

Referring to FIG. 2A, similar to the embodiment described above withrespect to FIG. 1A, a drug deactivation system may be implemented with adrug delivery device including a drug-retaining region 10 within which adrug 12 is retained. The drug deactivation system may include aplurality of capsules 14 configured as exemplarily discussed above withrespect to FIGS. 1A and 1B. The capsules 14 may retain an agent 16therein, which is also configured as exemplarily discussed above withrespect to FIGS. 1A and 1B. In the illustrated embodiment, however, thecapsules 14 are distributed along the periphery of the drug-retainingregion 10. As exemplarily illustrated, the capsules 14 may be spacedapart from each other along the periphery of the drug-retaining region10. Accordingly, the capsules 14 may be considered as partiallyenclosing the periphery of the drug-retaining region 10. In anotherembodiment, however, the capsules 14 may contact each other along theperiphery of the drug-retaining region 10 so as to completely enclosethe periphery of the drug-retaining region 10. Referring to FIG. 2B thecapsules 14 shown in FIG. 2A become degraded upon receiving energy inthe manner described above with respect to FIG. 1B.

In one embodiment, the capsules 14 are disposed adjacent to a structuredefining the periphery of the drug-retaining region 10. In anotherembodiment, the capsules 14 may be adhered to the structure defining theperiphery of the drug-retaining region 10. In yet another embodiment,one or more of the capsules 14 may also be dispersed throughout thedrug-retaining region 10 in the manner described above with respect toFIGS. 1A and 1B.

FIGS. 3A and 3B are plan views schematically illustrating an exemplaryembodiment of a drug deactivation system according to anotherembodiment.

Referring to FIG. 3A, similar to the embodiment described above withrespect to FIGS. 1A and 2A, a drug deactivation system may beimplemented with a drug delivery device including a drug-retainingregion 10 within which a drug 12 is retained. The drug deactivationsystem may include a single capsule 14′ configured in a similar manneras exemplarily discussed above with respect to FIGS. 2A and 2B, butshaped to completely enclose the periphery of the drug-retaining region10. In another embodiment, however, the single capsule 14′ may partiallyenclose the periphery of the drug-retaining region 10. Referring to FIG.3B the capsule 14′ shown in FIG. 3A becomes degraded upon receivingenergy supplied in a manner similar to that described with above respectto FIG. 2B.

In one embodiment, the capsule 14′ is disposed adjacent to a structuredefining the periphery of the drug-retaining region 10. In anotherembodiment, the capsule 14′ may be adhered to the structure defining theperiphery of the drug-retaining region 10. In yet another embodiment,one or more of the capsules 14 may also be dispersed throughout thedrug-retaining region 10 in the manner described above with respect toFIGS. 1A and 1B.

According to the embodiment exemplarily described above with respect toFIGS. 3A and 3B, agent 16 is released into the drug 12 within thedrug-retaining region 10 when the capsule 14′ degrades, therebyrendering the drug 12 ineffective. Thus, as exemplarily described above,the drug 12 may be rendered ineffective when the agent 16 binds to thedrug 12, when the agent 16 binds to receptors of the drug 12 or when theagent 16 chemically degrades the drug 12. In another embodiment,however, the drug 12 may be rendered ineffective when the drug 12 isphysically incapable of being removed from the drug-retaining region 10.In such an embodiment, the agent 16 contained within the capsule 14′ maybe provided as a material (e.g., a polymer) capable of physicallyencapsulating the drug 12 within the drug-retaining region 12. Forexample, the capsule 14′ may release a polymer capable of crosslinkingupon exposure to moisture (e.g., a cyanoacrylate) or a polymer capableof crosslinking upon exposure to UV light (e.g., an epoxy). In oneembodiment, polymer material of the agent 16 may further be capable ofbonding to sidewalls of the drug-retaining region 10, thereby makingextraction of the drug 12 difficult. In another embodiment, polymermaterial of the agent 16 may further be capable of penetrating intoand/or encapsulating material forming the drug retaining region 10,thereby rendering the drug 12 inaccessible to chemical extractionmechanisms. In such an embodiment, the material forming thedrug-retaining region 10 may be provided as a material such as a solidor gel having either nonporous or porous structures.

FIGS. 4A and 4B are plan views schematically illustrating an exemplaryembodiment of a drug deactivation system according to anotherembodiment.

Referring to FIG. 4A, a drug deactivation system may be implemented witha drug delivery device including a plurality of drug-retaining regions10 within which a drug 12 is retained. In the illustrated embodiment,the drug deactivation system may include a plurality of capsules 14″exposed to the plurality of drug-retaining regions 10. The capsules 14″may be configured as exemplarily discussed above with respect to FIGS.1A and 1B. The capsules 14″ may retain an agent 16 therein, which isalso configured as exemplarily discussed above with respect to FIGS. 1Aand 1B.

Collectively, the capsules 14″ and the drug-retaining regions 10 may bearranged in an array within the drug-delivery device. However, asexemplarily illustrated, the capsules 14″ and the drug-receiving regions10 may be substantially randomly distributed within the array. Inanother embodiment, the capsules 14″ and the drug-receiving regions 10may be substantially regularly distributed within the array.

As exemplarily illustrated, the shape of each of the capsules 14 may besubstantially the same as the shape of each of the drug-retainingregions 10. In another embodiment, however, at least one of the capsules14 and at least one of the drug-retaining regions 10 may havesubstantially the same shape.

As exemplarily shown, some of the drug-retaining regions 10 are adjacentto one or more capsules 14″ and some of the drug-retaining regions 10are adjacent to one or more other drug-retaining regions 10. A membrane22 may be interposed between adjacent ones of the drug-retaining regions10. In one embodiment, each membrane 22 may comprise the same materialas the capsules 14″.

Referring to FIG. 4B the capsules 14″ shown in FIG. 4A become degradedupon receiving energy in the manner described above with respect to FIG.1B, thereby forming degraded capsules 18″. In one embodiment, thecapsules 14″ shown in FIG. 4A become degraded upon receiving energy(e.g., chemical energy). In embodiments where the membrane 22 comprisesthe same material as the capsules 14″, the membranes 22 may be also bedegraded upon receiving energy, thereby forming degraded membranes 22″.Agent 16 may be released from the capsules 14″ and also be transferredthrough the degraded membranes 22″.

According to the embodiments exemplarily described above with respect toFIGS. 1A-4B, the capsules 14, 14′ and 14″ contain agent 16 that isreleasable into the drug 12, which is retained within the drug-retainingregion 10, when the capsules are degraded. In another embodiment,however, the capsules 14, 14′ and 14″ may contain the drug 12 and thedrug-retaining region 10 may retain the agent. In such an embodiment,the drug 12 may be released into agent 16 when the capsules 14, 14′ and14″ are degraded. In one embodiment, drug 12 released from the degradedcapsules may migrate within the agent 16 via self-diffusion orforced-diffusion (e.g., within a chemical gradient, a force gradient, anelectrical potential gradient, or the like or a combination thereof).

As mentioned above, capsules may be degraded upon receiving energy froman energy source. Energy capable of degrading the plurality of capsulesmay include electrical energy, thermal energy, chemical energy,mechanical energy, electromagnetic radiation, magnetic energy, or thelike or a combination thereof. In one embodiment, the energy source maybe comprised as a part of the drug delivery device. In anotherembodiment, the energy source may be provided separately from the drugdelivery device. For example, if the capsules described above aredegradable in the presence of thermal energy such as heat, then theenergy source could be a hair dryer supplied by the user of the drugretained within the drug-retaining region or somebody other than theuser. In one embodiment, the energy may be supplied to theaforementioned capsules 14, 14′ and 14″ manually by the user of the drug12 retained within the drug-retaining region 10 (or somebody other thanthe user). In another embodiment, the energy may be supplied to theaforementioned capsules 14, 14′ and 14″ automatically when apredetermined condition has been satisfied after detecting acharacteristic of the user, a characteristic of the drug-retainingregion, a characteristic of a user-engageable element of the drugdelivery device, a characteristic of a region external to the drugdelivery device and the user, or the like or a combination thereof. Anexemplary discussion of such detection and automatic supplying of energycan be found in the aforementioned co-pending U.S. patent applicationSer. No. 12/356,824, entitled “SENSOR SYSTEM FOR DRUG DELIVERY DEVICE,DRUG DELIVERY DEVICE HAVING THE SAME AND METHOD OF USING THE SAME.”

As mentioned above, energy capable of degrading the capsules 14, 14′ and14″ may include electrical energy. Various types of electrical energymay be may be applied to degrade the capsules 14, 14′ and 14″. In oneembodiment, a localized electric current or electric field may be usedto create a change in the solubility of the material from which thecapsule is formed. The generation of reducing or oxidizing agents cansignificantly change local solubility. Capsules 14, 14′ and 14″ may beformed of a material such as polylactic-co-glycolic acid (PLGA), whichis a biodegradable polymer that is insoluble in neutral to acidic pHconditions. By reducing the capsule's environment with a predeterminedreduction reaction at a cathode, one can selectively increase the pH topromote PLGA solubility. Upon detection of a breach by the sensor, theagent 16 may be released when electrical energy is applied at thecathode. This causes a reduction reaction to occur, making the capsule'senvironment more basic and thereby increasing the solubility of the PLGAmaterial of the capsules 14, 14′ and 14″. By increasing the solubilityof the material from which the capsules 14, 14′ and 14″ are formed, thecapsules 14, 14′ and 14″ may degrade by dissolving, thereby releasingthe agent 16 into the drug-retaining region 10.

The solubility of the material from which the capsules 14, 14′ and 14″are formed may also be changed in other ways. In another embodiment, thecapsules 14, 14′ and 14″ may be fabricated using a bi-layer constructionincluding an inner layer and an outer layer. The inner layer of each ofthe capsules 14, 14′ and 14″ may be soluble in the environment, and theouter layer may be normally insoluble in the environment. The outerinsoluble layer may be dissolved by application of an electricalpotential that oxidizes the outer layer. For example, an outer gold (Au)layer may be dissolved by the application of a voltage in the presenceof a chloride solution (Au+4Cl—→AuCl4—+3e− (˜1.1V, ˜0.1 M chloridesolution)). Once the outer Au layer is dissolved, the soluble innerlayer is exposed to the environment and readily dissolves, releasing theagent 16 into the drug-retaining region 10.

Electrical energy may alternatively be applied to cause a change in gaspressure within the capsules 14, 14′ and 14″ that causes the capsules14, 14′ and 14″ to degrade by rupture. For example, localizedelectrochemistry may be used to cause hydrolysis of water within thecapsules 14, 14′ and 14″. By applying an electrical energy in the formof a voltage applied across the capsules 14, 14′ and 14″, a current isproduced that breaks the water within the capsule into its constituentparts: hydrogen gas and oxygen gas. The gas pressure within the capsules14, 14′ and 14″ is thereby increased, causing the capsules 14, 14′ and14″ to degrade by rupture. The agent 16 is thereby released into thedrug-retaining region 10, where it can mix with the drug 12 and renderit ineffective.

As mentioned above, energy capable of degrading the capsules 14, 14′ or14″ may include electromagnetic radiation. For example, the capsules 14,14′ and 14″ may be composed of materials sensitive to variouswavelengths of electromagnetic radiation such that, in the presence of aparticular wavelength of electromagnetic radiation (e.g., microwaveradiation, infrared radiation, visible light, ultraviolet radiation, orthe like or a combination thereof), the capsules 14, 14′ and 14″degrades. In one embodiment, the capsules 14, 14′ and 14″ may be formedof a polymer material capable of absorbing light in the infrared range.The capsule material could then be heated directly by a source ofelectromagnetic radiation (e.g., microwave radiation, infraredradiation, visible light, ultraviolet radiation, or the like or acombination thereof) coupled to the drug delivery device. In oneembodiment, the source of electromagnetic radiation may include aninfrared light source (e.g., an aluminum-gallium-arsenic light emittingdiode) coupled to the drug delivery device. In another embodiment, thecapsules 14, 14′ and 14″ may be formed of a material that is relativelyinsensitive to light in the infrared range, but be coated with asupplemental coating capable of absorbing light in the infrared range.The capsule material could then be heated indirectly by the infraredlight source via the supplemental coating. When the capsule material issufficiently heated, a phase change (e.g., melting or vaporization)within the capsule material occurs and the capsule 14, 14′ or 14″ isdegraded to release the agent 16.

In another embodiment, the agent 16 itself may be sensitive toparticular wavelengths of electromagnetic radiation (e.g., microwaveradiation, infrared radiation, visible light, ultraviolet radiation, orthe like or a combination thereof). Accordingly, one or more lightsources configured to emit light at one or more of the particularwavelengths of light may be coupled to the drug delivery device. Whilethe example of an infrared light source and a capsule material orcoating sensitive to infrared light is given, a person of skill in theart will recognize that any combination of electromagnetic radiationsource and capsule material/coating/agent sensitive to that wavelengthmay be used.

As mentioned above, energy capable of degrading the capsules 14, 14′ or14″ may include thermal energy. In an exemplary embodiment, thermalenergy may be supplied to the capsules 14, 14′ and 14″ using one or moreheating elements disposed on the inside or the outside of the capsules14, 14′ and 14″. In one embodiment, a heating element may be provided asa resistive heaters (e.g., patterned resistors). The patterned resistorsmay be used for resistive (I²R) heating, causing the material from whichthe capsule is formed to degrade by either thermal stress due to rapidheating or cooling (e.g., thermal shock, thermal stress due to thermalexpansion coefficient mismatch or stresses induced due to volumetricchanges associated with phase changes). If the capsule material has ahigh coefficient of thermal expansion and is brittle, rapid heating mayalso cause the capsule to degrade by fracture, so that the capsule iscracked open. The agent 16 is thereby released into the drug-retainingregion 10, allowing it to mix with the drug 12 and render the drug 12ineffective.

In another embodiment, thermal energy may be applied to induce a phasechange (e.g., via boiling, vaporizing, etc.) within the agent 16 itself,causing the agent 16 to transition from a liquid phase to a gaseousphase. In such an embodiment, the internal pressure within the capsule14, 14′ or 14″ increases, causing the capsule 14, 14′ or 14″ to degradeby rupture. Upon rupture, the agent 16 is released into thedrug-retaining region 10, where it can combine with the drug 12 andrender the drug ineffective. In another embodiment, the capsule 14, 14′or 14″ may contain a secondary chemical that may undergo a phase changesufficient to rupture the capsule 14, 14′ or 14″. Accordingly, thecapsule 14, 14′ or 14″ may be ruptured due to the phase change of thesecondary chemical instead of (or in addition to) the agent 16.

As mentioned above, energy capable of degrading the capsules 14, 14′ or14″ may include chemical energy. For example, in the drug deactivationsystem exemplarily described above with respect to FIGS. 4A and 4B, thecapsules 14″ and/or the membranes 22 may be degraded by a chemicalreaction such as dissolution when, for example, the drug delivery deviceis immersed in water or other solution or solvent.

As mentioned above, energy capable of degrading the capsules 14, 14′ or14″ may include mechanical energy. For example, in the drug deactivationsystem exemplarily described above with respect to FIGS. 4A and 4B, thecapsules 14″ and/or the membranes 22 may be degraded by beingmechanically separated from each other when, for example, the drugdelivery device is immersed in water or other solution or solvent. Uponbeing mechanically separated from each other, the agent 16 mixes withthe drug 12, thereby rendering the drug 12 ineffective.

In another example, the drug delivery device may include a spring-loadedpiercing mechanism housed in the drug delivery device, which can degrade(i.e., pierce) the capsule 14, 14′ or 14″ when the spring is released.This mechanical force releases the agent 16 from the capsule 14, 14′ or14″ and into the drug-retaining region 10, where it combines with thedrug 12 and renders it ineffective.

Alternatively, acoustic energy may be focused on the capsules 14, 14′ or14″. In this manner, the acoustic force operates as a mechanical energywhich ruptures or otherwise degrades the capsule 14, 14′ or 14″. Forexample, an acoustic source may be integrated onto the backside of thecapsule 14, 14′ or 14″, or at a periphery of the drug-retaining region10. The acoustic energy source may be activated to degrade the capsules14, 14′ or 14″ and release agent 16 into the drug-retaining region 10.Lens designs can be used to focus the acoustic energy as an acousticforce on the capsule 14, 14′ or 14″, thereby imparting a mechanicalenergy on the capsule 14, 14′ or 14″ to rupture or otherwise degrade thecapsule 14, 14′ or 14″. If the acoustic energy is focused over a largedepth of field, multiple capsules 14, 14′ or 14″ may be ruptured orotherwise degraded simultaneously.

As mentioned above, energy capable of degrading the capsules may includemagnetic energy. For example, the capsules 14, 14′ or 14″ may havemagnetic shape memory (MSM) alloys incorporated therewith. MSM alloysare smart materials which can undergo large reversible deformations inan applied magnetic field, for example, Ni₂MnGa. By incorporating theseMSM materials with the capsule 14, 14′ or 14″, the capsule 14, 14′ or14″ may be capable of undergoing critical strains and stresses when amagnetic field is applied, allowing the capsule 14, 14′ or 14″ todegrade through rupturing or cracking.

According to the embodiments exemplarily described above with respect toFIGS. 1A-4B, energy is applied to one or more capsules 14, 14′ or 14″ todegrade the capsules 14, 14′ or 14″. When the capsules 14, 14′ or 14″are degraded, an agent 16 is provided to render a drug 12 ineffective.Thus, the drug 12 may be rendered ineffective when energy is applied toone or more capsules 14, 14′ or 14″. In other embodiments, however, thedrug 12 may be rendered ineffective without the need for any capsule 14,14′ or 14″. For example, a drug deactivation system may include at leastone energy source configured to transmit energy (e.g., electricalenergy, electromagnetic energy, thermal energy, or the like or acombination thereof) to the drug 12 retained within the drug-retainingregion 10. Upon receiving the energy, the drug 12 is renderedineffective. Exemplary drug deactivation systems according to suchembodiments, will now be discussed with reference to FIGS. 5 and 6.

Referring to FIG. 5, a drug deactivation system may include plurality ofenergy sources 50 coupled to the drug-retaining region 10. In oneembodiment, the energy sources 50 may be disposed within a housing ofthe drug delivery device, along with the drug-retaining region 10. Theenergy sources 50 may be configured to transmit energy to the drug 12retained within the drug-retaining region 10 to render the drug 12ineffective. Although FIG. 5 illustrates a four energy sources 50disposed approximately equidistant from each other, it will beappreciated that any number of energy sources 50 (i.e., one or more) maybe used and arranged as desired.

In one embodiment, one or more energy sources 50 may be configured toapply mechanical energy (e.g., in the form of acoustic waves) to thedrug 12 retained within the drug-retaining region 10 to render the drug12 ineffective. For example, one or more energy sources 50 may beprovided as an ultrasonic transducer disposed in communication with thedrug 12 retained within the drug-retaining region 10 to generateacoustic waves within the drug 12. In embodiments where the drug 12 isrendered ineffective upon the application of acoustic waves, the drug 12may, for example, be capable of undergoing an irreversible phasetransformation to become crystallized. When the drug 12 is crystallized,the drug 12 is converted to an insoluble form and is, therefore,ineffective to the user. In another example, acoustic waves generated byone or more energy sources 50 may generate ultrasonic waves within thedrug 12 and heat the drug 12. When the drug 12 is sufficiently heated,the drug 12 is rendered ineffective within the drug-retaining region 10.In one embodiment, the ultrasonic waves generated may both crystallizeand heat the drug 12 within the drug-retaining region 10.

In one embodiment, one or more energy sources 50 may be configured toapply electrical energy to the drug 12 retained within thedrug-retaining region 10 to render the drug 12 ineffective. Accordingly,one or more energy sources 50 may be provided as electrodes (e.g.,carbon electrodes) disposed in electrical communication with the drug 12retained within the drug-retaining region 10. Upon applying a sufficientvoltage to the electrodes, the drug 12 may undergo an electrochemicalreaction to produce hydrogen peroxide (H₂O₂). The H₂O₂ may then oxidizethe drug 12 within the drug-retaining region 10. Other possibleoxidizing agents that could be created electrochemically include OH.radicals formed from water molecules and hypochlorite electrogeneratedfrom any chloride ions of the drug 12. In another example, either thedrug 12 itself may dissociate or a drug matrix associated with the drug12 may undergo electrolysis, wherein the free oxygen or hydrogen gasproduced by the electrolysis may render the drug 12 ineffective.

Referring to FIG. 6, a drug deactivation system may further include anabsorbing element 60 disposed within the drug-retaining region 10. Eachof the energy sources 50, as similarly described above with respect toFIG. 5, may be provided as an electrode electrically connected to theabsorbing element 60. The absorbing element 60 is configured to absorbthe drug 12 in the presence of a voltage applied from the electrodes.When the drug 12 is absorbed by the absorbing element 60, release of thedrug 12 from within the drug-retaining region 10 can be significantly orcompletely prevented. In one embodiment, the absorbing element 60 may beprovided as an activated carbon network (e.g., an activated carbonfabric) disposed within the drug-retaining region 10. Although FIG. 6illustrates wherein the absorbing element 60 completely surrounds theperiphery of the drug-retaining region 10, it will be appreciated thatthe absorbing element 60 may partially surround the periphery of thedrug-retaining region 10. It will also be appreciated that a pluralityof absorbing elements 60 may be provided, each connected to the same orto different electrodes.

In embodiments where the drug 12 is a cationic drug, a positive voltage,(e.g., about +0.1V to about +0.5 V) may be applied from the electrodesto the absorbing element 60 to prevent absorption of the drug 12 duringnormal use. However, if a predetermined condition has been satisfiedafter detecting a characteristic of the user, a characteristic of thedrug-retaining region, a characteristic of a user-engageable element ofthe drug delivery device, a characteristic of a region external to thedrug delivery device and the user, or the like or a combination thereof,the electrodes may discontinue applying the voltage to the absorbingelement 60, or may reverse the polarity of the voltage applied to theabsorbing element 60. Upon discontinuing application of, or reversingthe polarity of, a voltage to the absorbing element 60, the drug 12 isabsorbed by the absorbing element 60 and is thereby renderedineffective. In embodiments where the drug 12 is an anionic drug,voltages of opposite polarities would be applied to the absorbingelement 60.

Referring back to FIG. 5, one or more energy sources 50 may beconfigured to apply electromagnetic radiation (e.g., microwaveradiation, infrared radiation, visible light, ultraviolet radiation, orthe like or a combination thereof) to the drug 12 retained within thedrug-retaining region 10 to render the drug 12 ineffective. For example,one or more energy sources 50 may be provided as a light-emittingelement (e.g., an LED) disposed in optical communication with the drug12 retained within the drug-retaining region 10. In embodiments wherethe drug 12 is rendered ineffective upon the application of ultravioletlight, the drug 12 may include a material such as an alcohol.

In yet another embodiment, one or more energy sources 50 may beconfigured to apply thermal energy (i.e., heat) to the drug 12 retainedwithin the drug-retaining region 10 to render the drug 12 ineffective.In one embodiment, one or more energy sources 50 may be provided as alight-emitting element (e.g., an LED) disposed in optical communicationwith the drug 12 retained within the drug-retaining region 10 and becapable of emitting electromagnetic radiation suitable for heating thedrug 12 within the drug-retaining region 10. In another embodiment, oneor more energy sources 50 may be provided as a heating element (e.g., aresistive heater) disposed on the inside or the outside of thedrug-retaining region 10. In embodiments where the drug 12 is renderedineffective upon the application of heat, the drug 12 may be aprotein-based drug.

It will be appreciated that several of the above-disclosed and otherfeatures and functions, or alternatives thereof, may be desirablycombined into many other different systems or applications. It will alsobe appreciated that various presently unforeseen or unanticipatedalternatives, modifications, variations, or improvements therein may besubsequently made by those skilled in the art which are also intended tobe encompassed by the following claims.

1. A drug deactivation system, comprising: at least one capsule exposedto at least one drug-retaining region of a drug delivery device, whereinthe at least one capsule is degradable; and an agent configured torender the drug ineffective upon degradation of the at least onecapsule, wherein the at least one drug-retaining region is configured toretain one of the drug and the agent, and wherein the at least onecapsule is configured to retain the other of the drug and the agent. 2.The drug deactivation system of claim 1, wherein the at least onecapsule includes a plurality of capsules.
 3. The drug deactivationsystem of claim 2, wherein the plurality of capsules are dispersedthroughout the at least one drug-retaining region.
 4. The drugdeactivation system of claim 2, wherein the at least one drug-retainingregion includes a plurality of drug-retaining regions, wherein theplurality of capsules and the plurality of drug-retaining regions arearranged in an array within the drug-delivery device and wherein theplurality of capsules and the plurality of drug-retaining regions arerandomly distributed within the array.
 5. The drug deactivation systemof claim 4, wherein at least two of the plurality of drug-retainingregions are adjacent to one another, the drug deactivation systemfurther comprising: a membrane interposed between the at least two ofthe plurality of drug-retaining regions, wherein at least one of theplurality of capsules and the membrane comprise the same material. 6.The drug deactivation system of claim 1, wherein the at least onecapsule encloses at least a portion of a periphery the at least onedrug-retaining region.
 7. The drug deactivation system of claim 6,wherein the agent comprises a material capable of physicallyencapsulating the drug within the drug-retaining region.
 8. The drugdeactivation system of claim 1, wherein the at least one capsule isexposed to a plurality of drug-retaining regions of the drug deliverydevice.
 9. The drug deactivation system of claim 1, wherein a shape ofthe at least one capsule is substantially the same as a shape of the atleast one drug-retaining region.
 10. The drug deactivation system ofclaim 1, wherein the at least one capsule includes a porous materialthat chemically binds the agent.
 11. The drug deactivation system ofclaim 1, wherein the at least one capsule is degradable in the presenceof at least one selected from the group consisting of electrical energy,thermal energy, chemical energy, mechanical energy, electromagneticradiation, and magnetic energy.
 12. A method of deactivating a drug, themethod comprising: exposing at least one capsule to at least onedrug-retaining region; and degrading the at least one capsule, whereinthe at least one drug-retaining region retains one of a drug and anagent configured to render the drug ineffective, wherein the at leastone capsule retains the other of the drug and the agent, and wherein thedrug is exposed to the agent when the at least one capsule is degraded.13. The method of claim 12, wherein degrading the at least one capsulecomprises exposing the at least one capsule to at least one selectedfrom the group consisting of electrochemical energy, thermal energy,mechanical energy, electromagnetic radiation, and a magnetic field. 14.The method of claim 13, wherein degrading the at least one capsulecomprises exposing the at least one capsule to electrical energysufficient to alter a solubility of a material forming the at least onecapsule.
 15. The method of claim 13, wherein degrading the at least onecapsule comprises exposing the at least one capsule to thermal energysufficient to induce a phase change within a material forming the atleast one capsule.
 16. The method of claim 13, wherein degrading the atleast one capsule comprises exposing the at least one capsule tomechanical energy selected from the group consisting of a physical forceand an ultrasonic wave.
 17. The method of claim 13, wherein degradingthe at least one capsule comprises exposing the at least one capsule toelectromagnetic radiation selected from the group consisting ofmicrowave radiation, infrared radiation, visible light, ultravioletradiation, or a combination thereof.
 18. The method of claim 13, whereindegrading the at least one capsule comprises exposing the at least onecapsule to a magnetic field sufficient to deform the at least onecapsule.
 19. A drug deactivation system comprising: an agent configuredto render a drug ineffective; and a capsule, wherein the capsule isdegradable, and wherein the capsule is configured to isolate the drugfrom the agent when the capsule is in a substantially non-degradedstate.
 20. The drug deactivation system of claim 19, wherein the capsulecomprises a material capable of degrading in the presence of at leastone selected from the group consisting of electrical energy, thermalenergy, chemical energy, mechanical energy, electromagnetic radiation,and magnetic energy.